After centuries of "Eurocentric" linguistic ideology, the South African government has formulated African language development and multilingualism as one priority in the education system. While only English, and decreasingly Afrikaans, are the only "established" languages of instruction at tertiary level, most universities in the country have revised their language policies in order to show commitment to South Africa's evident multilingualism. This article provides a critical analysis of particular language and identity politics in one of the leading tertiary institutions of the country. The theoretical framework is based on a critical sociolinguistic approach that draws attention to polarizing identity politics in relation to language policy, planning and implementation. Methodologically grounded in ethnography, the article has a two-fold perspective. First, it analyses particular language policy rhetoric at the University on focus and argues that its essentialist approach to Africanisation triggers contested identity politics. Second, the article provides insights into the developments of specific implementations, pointing to ideological as well as practical challenges at the university on focus.